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It will of course take off, even assuming the treadmill is the size of a real landing strip (which is part of the original supposition).

The wheels do not move the plane, nor create lift. They are incidental to the aircraft’s takeoff. The propellers or jet engines create the forward force. Other than spinning madly (or not moving at all, depending on how the question is worded), it will have no effect on the takeoff, which would occur normally.

Why would the wings break off? It would actually go away from the control panel. Maybe, if you turned the plane around and gave a little more incline (away from the control panel), you’d get a bit of distance.

Kero, why would it go forward? Do you run backwards on the treadmill? No. See the video or animated GIF of the girl busting her ass on a treadmill. NOTE: she doesn’t go forward, her legs don’t break off, BUT it IS damn funny.

I don’t get the debate; how could it possibly be able to take off? Assuming it could get enough propulsion to counteract the motion of the treadmill, it still wouldn’t be able to take off since the treadmill isn’t nearly long enough for the plane to be able to accellerate enough to generate lift. And assuming it somehow would be able to, it would either have to instantly tilt upwards at almost a 90 degree angle in order to clear the control panel and stand, or rotate dramatically along the chassis to avoid having the wings completely sheared off.

And Kero: You actually aren’t moving (at least in the sense that would be relative to this conversation) when you’re running on a treadmill. Of course this is relative, so it might be best to say that you aren’t moving in relation to the earth, which a plane would need to be in order to create resistance against the wind and thus take off.

It won’t take off. Anyone who remembers the least bit of Physics could tell you why.

Lift is created by a pressure differetial between the top and bottom of the wing, created by the difference in length of travel of air over the wing. It’s called Bernouli’s Priciple.

Since in this case, there would be little to no airflow over the wings, no lift would be created. The wheels can spin all damn day, and if there’s no lift, no takeoff.

The whole purpose of wheels on a plane is to reduce friction between the ground and plane, making it much easier to acheive the AIR SPEED required for the lift needed for takeoff, with much less thrust (forward propulsion) than if you had the plane mounted on skids. Of course, wheels make for a much nicer landing, too.

I know that some people are just kidding with their comments, but still.

What would be a reasonable situation to ponder would be the same airframe in front of a large fan, and the question would be “Will it take off?”

That might have a shot at getting off the ground, but since the lift would be created all by the fan, and the plane would lack it’s own propulsion, it would likely lift off, then backflip or veer off and crash.

Ok. Imagine you have a hypothetical 2 miles long treadmill.
If the engines are set to full power the plane will simply push itself using the air around it(Thats how a jet engine works). The wheels will spin madly (due to speed relative to the earth+speed of the treadmill). However the engines and the lift generation component ignores the treadmill speed nearly completely. (the plane might be set a few hundred feet back at the start while spooling up the engines).
Given the fact that the wheels are there just to reduce friction (and they DO that, the plane wont take off if the brakes are on ), the plane will just take off ignoring the treadmill.

Wait no it doesnt. Assuming the wheels don’t break off because they would be skidding the plane would take off. Because the the jets that move the plane not the wheels. so the plane would go forward and the wheels would just skid across it and kind of break, and then the plane would crash. But if the wheels were hylothetically indistructable, then the plane would take off.

another thing to take into consideration is the immense thrust that is being shot out the back of the turbines, I dont know how much thrust exactly but i do know that the engines on full power, if left stationary for too long will eventually start ripping up the runway.. they are pretty damn powerful and this idea would just screw up the runway

Your answer would be correct if the forward thrust of the plane were being created by the wheels. Since the wheels are free spinning, and the thrust is being created by the engines, theoretically the plane can take off. Assuming that the treadmill was long enough, and that the thrust of the plane could overcome the extra resistance that would be put to the spinning wheels. That is of course assuming that the wheels can withstand the extreme spinning that would occur. An example would be if the tread was spinning at 12kph, and the plane tries to head forward at 12kph, the wheels would actually be spinning at like 24kph…(forgive me if the math is a bit off, but I’m just trying to prove the concept)

If we’re going out on limbs here, then yes, if you had a treadmill 1-2 miles long, and you had enough forward thrust to overcome the treadmill speed and still get enough forward air speed for the lift required for takeoff, then you could get this beast off the ground.

If you’re going to build a 2 mile long treadmill for this experiment, here’s a question…

Why not just build a damn runway?

It seems that whole posit is if you could somehow get it off the ground on an abbrevated runway using a treadmill or like device.

I say that the only way to shorten the length of ground required for takeoff is to either lighten the load so less lift is required, increase the forward thrust and air speed by some mechanism such as the JATO (Jet-Assisted Take Off) bottles that the military has in it’s inventory, or some combination of the two.

What could work is a treadmill went fast enough that you could achieve a ground speed comparable to the air speed required for takeoff. Then, the treadmill suddenly stopped or slowed considerably, transferring that ground speed into air speed and catapulting you forward. In doing such, you would place a tremendous “G” load on the airframe, and certainly the passengers. Imagine being shot from 0 to 130-150 MPH almost instantaneously.

Imagine you are standing still and step, feet planted firmly, onto a moving treadmill. You’d go shooting off the back, right? Some of us have had the pleasure of seeing this happen to someone. Well, if the opposite were true, and you were going really fast on the treadmill, and it suddenly stopped, you’d be fired off in a forward direction. This type of jolt would probably not be very healthy for a commercial plane or its passengers, but the steam catapults on aircraft carriers accelerate the planes to about 125 knots in a very short distance, so the concept has been adapted to practical use in a way.

Umm, so the answer to this puzzle depends on the exact wording of the question. I’ve seen it written two ways, and I’ve answered each below.

1) If the treadmill were designed to match the speed of the PLANE, it will take off. Say the plane is traveling at 100 mph (relative to the GROUND), then the treadmill will spin at 100 mph in the opposite direction, causing the wheels to spin at 200 mph. The wheel speed does not match the plane speed (or the treadmill speed); however, the plane is moving relative to the ground (and air–no magic lift here), and takes off.

2) If the treadmill is designed to match the speed of the WHEELS, the plane will not take off. The plane cannot move relative to the ground as long as the wheels are not sliding. (In the above example, the wheel speed can never be the same as the treadmill speed if the plane is moving relative to the ground) Of course, this would have to be some treadmill to accelerate and maintain speeds such that the small amount of force it generated against the plane through friction in the axles would counteract the huge amounts of thrust generated by the engines. Surely, this is not the intent of the question, but with this wording, it is the correct answer.

Assuming that wording #1 is the one most people are using (it’s certainly the more sensible of the two), then most people seem to make the mistake of thinking that speed of the plane is the wheel speed. But the only sensible reference for the speed of the plane is relative to the ground. So, if you’re holding on to the sides of a treadmill that traveling at 5mph while you are on a skateboard, you are motionless. Now, assuming that the treadmill is not banked, the force you need to move yourself forward (analogous to the thrust necessary to move the plane forward) is not much greater than if the treadmill were not on at all. It will be slightly greater, due to some friction in your wheel axles, but not much. Once you do begin moving forward, the speed of the treadmill is still 5 mph, but the wheel speed is now 5 mph plus however fast you’re going. The wheel speed is not the same as your speed.

So, put your skateboard on that conveyor runway, strap a jet engine to yourself, and I suspect you’ll move forward (relative to the ground) no matter how fast the runway moves. And so does the plane. Just so long as there is no specification that the runway moves as fast as your wheels.

It seems to me the essential question is “Can a plane take off (lift off) without moving forward (staying in place). Not with a treadmill. Maybe with a large fan blowing air over the wings… What if the wings moved by themselves, say, rotating around a central axis, thus generating air resistance that generates lift! Yeah, that would work! I think we should call this new idea “Helicopter”. Wait a second! There’s another way for this to work. If the jet engines actually swiveled to produce vertical thrust… it would be a feature that we could call “Vertical Take-Off Landing”, or VTOL for short.

Jesus, you expect that plane to take off?? Christ. You people think that planes take off, due to the wheels turning?? The wheels could be going 500mph, it would make shit all difference. Some of you need to go back to school.

People are getting quite vehement without realising that their opponents are answering a different question to them. There are two different questions here, and that is what is causing the confusion.

Q1. Can use of a treadmill allow a plane to take off without moving forward?

To which the answer, is, of course, no. You’d get no airspeed under and over the wings, hence no lift.

Q2. Can a plane take off if there is a treadmill under the wheels, spinning in the opposite direction to the planes movement, set to match the speed of the planes forward motion?

(This is (paraphrased) the original theoretical question asked, and upon which the above satirical picture was created. Some people are therefore answering this question, not the “face-value” question suggested by the picture.)

In this instance, the answer is yes, the plane can take off, since the speed of the treadmill will have zero effect on the planes forward motion. The plane will move forward just as it would on an ordinary runway, and thus take off as normal.

I don’t think that anyone here is stupid.
I think that many of you are confused, or not thinking long enough, but not stupid.
(Except possibly LordOpie. OK GO was not a long-lasting meme. Please try to get over it.)

1 – Survey The Situation
This picture is not meant as an exact diagram of the experiment, it is just a funny way to make us think about it.
The actual experiment refers to a runway-sized treadmill, with no handles or incline, with a plane moving in the opposite direction to its (the treadmill’s) motion.

2 – Biology 707
A car moves by pushing against the ground.
If you put a car on an appropriate treadmill, it would indeed stay in one place.
However, a plane pushes against the air, the wheels are there because if they weren’t, the plane would scrape along the ground, slowly grinding itself away. The wheels aren’t even connected to a motor.

3 – It All Comes Together
The plane is on the treadmill. The engines roar into life and push against the air. Eventually, the engines are generating so much thrust that the plane edges forward. The treadmill operators notice this, and start their contraption, only to watch hopelessly as the plane ignores them completely. For it is pushing against the air, not the ground. The plane eventually reaches the critical speed, and ascends, its pilot satisfied with a flawless takeoff.

I hope this has been of use to someone. In future, try not to put each other down so harshly. We’re all doing the best we can.

The engines push the plane and the air resistance against the wings causes the lift. Without the resistance generated by the motion of the plane the efforts of the engines are for nothing. Regardless of the size of the phantom treadmill or railings the plane would not take off. The concept contradicts the physics of flight.

Your implying that the plane would move along the treadmill because the wheels are there only to hold it up until the necessary air pressure is there. For your scenario to work the plane would need to go faster than the treadmill could compensate for right? Well that nullifies the entire experiment. The point was whether or not the plane would lift without forward motion. The answer is NO. If it were possible I’m sure we’d be seeing some very different looking airports.

I can’t believe this is still an issue. Of course the treadmill will take of, its got an airplane pushing it! Seriously, the plane would never leave the ground due to no air going across the wings, creating lift, which is how a plane flies, not by “Pushing air back.”

It’s sad that it takes 47 comments to resolve a question that should have taken 1. Whoever still thinks it’ll fly I will hunt down and beat with a physics book.
This had better be the last comment I see in this thread.

The people who say it will not take off wrongly assume that acceleration is in the wheels. Based off their assumption, if the wheels push the plane forward at 200 mph, and the treadmill moves back 200 mph, then the AIRSPEED will be 0 mph and the plane will obviously NOT take off. TREADMILLS DO NOT PUSH AIR!

However that is a wrong assumption.

The acceleration is in the jet propulsion, which is dependent on conservation of momentum, not tires. If the plane is being thrust forward 200 mph and the ground is moving back 200 mph, the ground speed will be 400!! mph and the airspeed will STILL be 200 mph (assuming friction of wheels on ground is negligible).

You can’t model an airplane on a treadmill like you model a car on a treadmill.

“When the treadmill starts to move back, the plane will also start to move back.”

The correct way to think about this, is if the plane is moving forward 10 mph based off thrust, and the treadmill starts spinning, the plane will still be moving forward 10 mph, but the tires will be spinning at 20 mph.

For fecks sake!!! Get it through your nullo-brainsacks, ground moving backwards threadmill-style will not slow down a plane in any way, It’ll just cause some heat through friction in the wheel base. Of course it will take off!

Sike Cecil’s answer says that the plane will take off on a treadmill that has enough length. The question here is if the plane will take off just from the treadmill going backwards and the plane pulling its self forward to keep up with the treadmill and it is an obvious that the answer is no, this is because if the plane is pulling itself forward enough to keep up with the treadmill (as a normal person running on a treadmill would do) then it is still stationary and there is no air running across the wings to create any lift.

How does a plane move? Force caused by it’s engines. The wheels have nothing to do with it. If they did, how would a water plane take off?

Think of it as if you replaced the wheels with skis. The plane would still take off just fine on a normal run way. On the treadmill, sure, the treadmill will spin the wheels backwards at some X speed, but the plane will still move forward regardless.

Well, Colin, your mama must have raised you on picturebooks, because the treadmill above is just a “funny” illustration of a scienific question that deals mainly with methods of propulsion. Of course the plane and threadmill shown above are not the actual ones meant in the thought experiment. If your train of logic were followed, the answer would be :”no, it is a toy plane and would not be capable of jet prpulsion”

Hmmm….i’m a pilot and i can say this…. an fixed wing aircraft will only take off if and only if there exist sufficent air movement (wind) aross the wing (thats what a wing does; it converts wind energy into lifting energy). A plane on a moving treadmill do not receive any wind for it to take off.

The engine does provide a small portion of lifting power. If you know anyting about vectors, you will notice that a componet from the engine’s power is pointed upwards, hence lift. However, this is only true when the engine is pointed above the horizon.

IT DOESNT MATTER WHAT THE WHEELS ARE DOING… Some planes dont have wheels –> flat planes and ski planes. Wind and wing is all that matters when it comes to take off. A plane can still take off if there is enough headwind even if the plane is stationary… try it on flight sim.

To, Ando… even if you set tte treadmill to 1000 mph, there is no wind across the wings for it to generate lift.

you know what brendan n. i want you to go put your head between you knees and suck ur balls in ur throat cuz u kno wat, THIS IS A WEBSITE DUMBASS WHO CARES, besides i was just posting a comment on this picture you dumbshit i dont see what the hell is wrong with you, cuz if you can find things i say funny then more power to ya, but if u dont idc, but if you dont and hace something to say about it then dont bitch and moan over teh internet bitch and moan about it in my face cuz this is a picture god dammit

You guys are all idiots. There is no way for it to take off. It would hit the damn poles. And lets say the poles were not there, there is no vertical lift because the plane isn’t actually going anywhere, there has to be forward motion for it to go anywhere.

holy fuck you guys are completely retarted, the fucken ariplane would definately NOT take off, because if you turn the treadmill on, the wheels would spin and NO air would move over the wings causing lift.

Let’s keep discussing what other’s can’t understand, it makes me feel better about myself. Especially when there are so many people who are smarter than me, it makes me feel good to read through post after post of others trying to wrap their heads around the obvious.

this airplane is made of plastic so it wont 😀
but in the scenario of the original question with a long long runway of treadmill, that goes in the opposite direction of the planes wheels, ofc it will take off 😀 the wheels and the runway will be spinning both, always accelerating, but a plane doesnt take off cause they taxi it along the runway..the condition tween wheels an runway is the same as tween a waterplanes lil skates and the water – the jet engines WILL make the plane go forward cause jet engines dont give a sh*t about wheels an runways, it just occupies itself with the system that is the air around the plane

I think everyone has figured out by now that about:
25% of this thread knows it will fly and just say it wont because they’re trolls.

25% know it will fly and are trying to fight the trolls, not realizing you can only kill a troll with fire, and the fires of a flamewar are insufficient. Or they are simply unaware that the other 25% are trolls.

50% of this thread has no idea whatsoever what is going on, they are just typing words because everyone else is.

This will not work because the only way the plane gets off the ground is by air resistance.

#2, the treadmill goes backwards. Even assuming that the jet’s engines are going fast enough to take off if the jet were on the ground, there is no wind for the wings to push off of to get lift off of the ground.